Climate and Water Monitoring at Carlsbad Caverns National Park: Water Year 2024
Kristina Fahey, Kara Raymond, Tani Hubbard
Please cite this publication as:
Fahey, K., K. Raymond, and T. Hubbard. 2026. Climate and Water Monitoring at Carlsbad Caverns National Park: Water Year 2024. Science Report NPS/SR—2026/484. National Park Service, Fort Collins, Colorado. https://doi.org/10.36967/2318793
Abstract
The Chihuahuan Desert Inventory and Monitoring Network monitors climate and six springs each year at Carlsbad Caverns National Park, New Mexico. We report on climate and water resources together because surface water conditions are closely related to climate conditions. Climate data, including temperature, precipitation, and reconnaissance drought index, are retrieved from The Climate Analyzer (climateanalyzer.org). We assess the condition of each spring, measure spring discharge and wetted extent (area that contained water), collect core water quality and water chemistry data, note the wetland plants and invasive plants and animals present, and sample for environmental DNA (eDNA) to inventory springs for rare species, invasive species, and pathogens. Each spring is somewhat unique, and New Mexico has not adopted water quality standards that apply across the diversity of springs in the state. Therefore, we continue to collect water quality data at the springs to form a baseline reference of natural variance. There was less rainfall than average across WY2024, though October was very wet. The drought index indicated the park was drier than average for the third consecutive year. Overall, high and low temperatures were above normal, but highs varied by month. Wetted area was similar to prior years at all springs except Oak Spring where the springbrook was much shorter than previously measured, and the plunge pool was completely dry. Upper Lowe Ranch Spring has been wet year round since July of 2022, though one orifice was completely dry during the March 2024 visit. Rabbitsfoot grass, an invasive plant, was observed for the first time at Iron Pipe Seep. At Slaughter Pot Hole, Upper East Grammer Spring, and Upper Lowe Ranch Spring, we detected invasive Lehmann lovegrass for the first time. None of our eDNA target species were detected at any spring.
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Overview
Together, climate and hydrology shape ecosystems and the services they provide, particularly in arid and semi-arid ecosystems. Understanding changes in climate and surface water is key to assessing the condition of park natural resources—and often, cultural resources.
At Carlsbad Caverns National Park (Figure 1), Chihuahuan Desert Inventory and Monitoring Network scientists study how ecosystems may be changing by taking measurements of key resources, or “vital signs,” year after year—much as a doctor keeps track of a patient’s vital signs. This long-term ecological monitoring provides early warning of potential resource problems, allowing managers to mitigate them before they become worse. At Carlsbad Caverns National Park, we monitor climate and springs, among other vital signs. Surface water conditions are closely related to climate conditions. Because they are better understood together, we report on climate in conjunction with water resources. Reporting is by water year (WY), which begins in October of the previous calendar year and goes through September of the water year (e.g., WY2024 runs from October 2023 through September 2024). In this report, we present the results of climate and springs monitoring at Carlsbad Caverns National Park in WY2024.
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Climate and Weather
There is often confusion over the terms “weather” and “climate.” In short, weather describes short-term meteorological conditions (e.g., it’s currently raining or snowing, it’s a hot or frigid day), and climate reflects patterns of weather at a given place over longer periods of time (seasons to years). Climate is the primary driver of ecological processes on Earth. Climate and weather information provide context for understanding the status or condition of other park resources.
Methods
A National Oceanic and Atmospheric Administration Cooperative Observer Program (NOAA COOP) weather station (Carlsbad Caverns #291480) has been operational at Carlsbad Caverns National Park since 1935 (see Figure 1). This station typically provides a reliable climate dataset, but in WY2024 it was missing data on 81 days. As a substitute, climate analyses in this report use WY2024 and 30-year averages (1991–2020) of gridded surface meteorological (GRIDMET) data from the location of the station. Subsequent reports may revert to the weather station as the data source depending on future data quality.
GRIDMET is a spatial climate dataset (4-kilometer resolution) that is interpolated using weather station data, topography, and other observational and modeled land surface data. Temperature and precipitation estimated from GRIDMET may vary from actual weather at a particular location depending on the availability of weather station data and the difference in elevation between the location of interest and that assigned to a grid cell. Data from both the weather station and GRIDMET are accessible through The Climate Analyzer.
Results
Precipitation and Air Temperature
Highlights: It was drier than average across the year, except for a very wet October. Overall, high and low temperatures were above normal, but highs varied by month.
Annual precipitation at Carlsbad Caverns National Park in WY2024 was 10.13″ (25.73 cm), 4.58″ (11.63 cm) less than the 1991–2020 annual average. The October precipitation total (Figure 2) was approximately twice the 1991–2020 average. All other months were drier than average. The largest monthly precipitation deficits relative to average occurred in May and September, which had 1.24″ (3.15 cm) and 1.58″ (4.01 cm) less rain than average, respectively (Figure 2). The mean annual maximum temperature in WY2024 was 75.7°F (24.3°C), 0.1°F (0.1°C) above the 1991–2020 average. The mean annual minimum temperature in WY2024 was 55.0°F (12.8°C), 3.8°F (2.1°C) above average. Mean monthly maximum and minimum temperatures in WY2024 differed by as much as 5.9°F (3.3°C; see August as an example) relative to the 1991–2020 monthly averages (Figure 2). Mean monthly maximum temperatures oscillated above and below the 30-year averages all year. Mean monthly minimum temperatures were warmer than average in every month except January.
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Drought
Highlight: The park was drier than average for the third consecutive year.
Reconnaissance drought index (Tsakiris and Vangelis 2005) provides a measure of drought severity and extent relative to the long-term climate. It is based on the ratio of average precipitation to average potential evapotranspiration (the amount of water loss that would occur from evaporation and plant transpiration if the water supply was unlimited) over short periods of time (seasons to years). The reconnaissance drought index for Carlsbad Caverns National Park indicates that WY2024 was drier than the 1991–2024 average for the third consecutive year from the perspective of both precipitation and potential evapotranspiration (Figure 3).
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Springs
Background
Springs, seeps, and tinajas (discrete pools in a rock basin or impoundments in bedrock) are small, relatively rare biodiversity hotspots in arid lands. They are the primary connection between groundwater and surface water and are important water sources for plants and animals. For springs, the most important questions we ask are about persistence (How long was there water in the spring?) and water quantity (How much water was in the spring?). WY2024 springs sampling at Carlsbad Caverns National Park occurred between 03 March and 18 March 2024. Water persistence is monitored continuously throughout the water year, but in this report, we only present WY2024 persistence data up to the sampling visit date for each spring.
Methods
Chihuahuan Desert Network springs monitoring is organized into the four modules described below (see McIntyre et al. 2018 for additional details) and eDNA inventories. All data have undergone certification processes to ensure they have been verified and validated for accuracy, are complete, and are fully documented. Data used in this report are available to park staff on the NPS DataStore and can be provided upon request.
Site Characterization
This module provides context for interpreting change in the other modules. We record GPS locations, draw a site diagram, and describe the spring type (e.g., helocrene, limnocrene, rheocrene, or tinaja) and its associated vegetation in this module. Helocrene springs emerge as low-gradient wetlands, limnocrene springs emerge as pools, and rheocrene springs emerge as flowing streams. This module is completed once every five years or after significant events.
Site Condition
We estimate the level of natural and anthropogenic disturbances and the level of stress on vegetation and soils at the spring on a scale of 1–4, where 1 = undisturbed, 2 = slightly disturbed, 3 = moderately disturbed, and 4 = highly disturbed. Types of natural disturbances can include flooding, drying, fire, wildlife impacts, windthrow of trees and shrubs, beaver activity, and insect infestations. Anthropogenic disturbances can include roads, off-highway vehicle trails, hiking trails, livestock and feral-animal impacts, removal of invasive non-native plants, flow modification, and other evidence of human use of the spring site. We take repeat photographs from the same location and perspective to show the spring and its landscape context. We note the presence of certain obligate wetland plant species (plant species that almost always occur only in wetlands), facultative wetland plant species (plant species that usually occur in wetlands, but also occur in other habitats), and invasive non-native crayfish and American bullfrog (Rana catesbeiana). We also record the density of invasive non-native plants using a qualitative scale (1–5 plants, scattered patches, evenly distributed patches, or a matrix). We complete the site condition module during each springs monitoring visit.
Water Quantity
We measure the persistence of surface water, amount of spring discharge, and wetted extent (area that contained water). To estimate persistence, we analyze the variance of temperature measurements taken by two logging thermometers placed at or near the orifice (spring opening). Because water mediates variation in diurnal temperatures, data from a submerged sensor will show less daily variation than data from an exposed, open-air sensor; this tells us when the spring was wet or dry. Surface discharge is measured with a timed sample of water volume. Wetted extent is a systematic measurement of the physical length (up to 100 m), width, and depth of surface water. It is assessed using a technique for either standing water (e.g., limnocrene and helocrene springs) or flowing water (e.g., rheocrene springs). We complete discharge and wetted extent measurements during each visit when possible. Water persistence measurements are continuous throughout the year.
Water Quality
We measure core water quality and water chemistry parameters. Core water quality parameters include water temperature, pH, specific conductivity (a measure of dissolved compounds and contaminants), dissolved oxygen (how much oxygen is present in the water), and total dissolved solids (an indicator of potentially undesirable compounds). Discrete measurements of these parameters are collected with a multiparameter meter. If the meter fails calibration checks, we do not present data. Water chemistry is assessed by collecting surface water samples and estimating the concentration of major ions with a photometer in the field. These parameters are collected at one or more sampling locations within a spring. Data are presented only for the primary sampling location within each spring. Each perennial spring is somewhat unique, and New Mexico has not adopted water quality standards that would apply across the diversity of springs described here. Ongoing, long-term data collection at each spring will improve our understanding of the natural range in water quality and water chemistry parameters for a given site. We complete the water quality module during each visit when possible.
eDNA Inventory of Rare and Invasive Species and Pathogens
We inventory rare species, invasive species, and pathogens in perennial springs using environmental DNA (eDNA) techniques. In 2023 and 2024, four or more water samples (250 mL/sample) were collected and filtered (0.45 µm) from each spring and then preserved in ethanol prior to DNA extraction and analysis by the Goldberg Lab at Washington State University. Our target organisms for the inventory include American bullfrog (Rana catesbeiana), chytrid fungus (Batrachochytrium dendrobatidis), ranavirus (Iridoviridae), red spotted toad (Bufo punctatus), Rio Grande leopard frog (Rana berlandieri), and Woodhouse’s toad (Anaxyrus woodhousii).
Results
Iron Pipe Seep
Highlights: The spring contained water when we visited but was dry for significant periods in WY2024. Discharge was much higher than average, and the wetted area was similar to prior years. We found rabbitsfoot grass, an invasive plant not previously observed at the spring.
Iron Pipe Seep (Figures 4 and 5) is a rheocrene spring (a spring that emerges into one or more stream channels) located in the upper elevations of an east-facing ridge overlooking West Slaughter Canyon below a rock outcrop. Cool, clear water trickles from a historical 1-inch-diameter pipe, protruding a few inches out from the hillside. It forms an intermittent channel that has measured up to 7.3 m (24.0 ft) long. Grasses, shrubs, and junipers dot the area immediately surrounding the spring. The WY2024 visit occurred on 16 March 2024, and the spring contained water.
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Site Condition
In WY2024, we rated Iron Pipe Spring moderately disturbed by flow modification because the primary source of flow is an iron pipe protruding from the bank. Tracks, game trails, and scat indicate wildlife is using the spring. No other natural or human-caused disturbances were observed at Iron Pipe Seep in WY2024.
As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Iron Pipe Seep in WY2024. We observed one invasive non-native plant species at the spring: scattered patches of annual rabbitsfoot grass (Polypogon monspeliensis, not previously observed).
We observed two obligate/facultative wetland plant species: a member of the rush family (Juncacaeae, observed in 2018–2023) and a sedge (Carex sp., observed in 2018–2022).
eDNA Inventory of Rare and Invasive Species and Pathogens
In WY2024, four water samples were collected from Iron Pipe Seep. None of our target organisms were detected. In WY2023, three water samples were collected, and red spotted toad (Bufo punctatus) was detected in one of the samples.
Water Quantity
Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 6). The temperature sensor indicated that Iron Pipe Seep was wetted (contained water) for 57 of 168 days (33.9%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 6.1–72.9% of the days measured across entire years.
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In WY2024 the estimated volumetric discharge was 3.0 ± 0.1 L/min (0.8 ± 0.03 gal/min), representing a substantial increase compared to a prior range of means between 0.0 and 0.3 L/min (0.0–0.1 gal/min) from 2018 to 2023 (Table 1). Wetted extent was evaluated using a method for flowing water. The total springbrook length was 6.4 m (21.0 ft), which falls within the historical range of 0.5–7.3 m (1.6–24.0 ft). In WY2024, width and depth along the springbrook averaged 21.4 cm (8.4 in) and 0.3 cm (0.1 in), respectively. Width in WY2024 was within the range of prior values, while depth was slightly lower than previously recorded (Table 2).
| Sampling Location | WY2024 Mean (Range of Prior Means) |
Prior Years Measured (# of Visits with Measurements) |
|---|---|---|
| 001 | 3.0 ± 0.1 (0.0–0.3) | 2018–2023 (6) |
| Measurement | WY2024 Value (Range of Prior Values/Means) |
Prior Years Measured (# of Visits with Measurements) |
|---|---|---|
| Width (cm) | 21.4 ± 32.8 (13.6–31.2) | 2018–2023 (6) |
| Depth (cm) | 0.3 ± 0.4 (0.4–0.7) | 2018–2023 (6) |
| Length (m) | 6.4 (0.5–7.3) | 2018–2023 (6) |
Water Quality
Core water quality (Table 3) and water chemistry (Table 4) data were collected at the primary sampling location in WY2024, directly from the iron pipe. Dissolved oxygen, pH, and water temperature were within the ranges of previously recorded values (2018–2023), while specific conductivity and total dissolved solids were slightly lower. Levels of alkalinity, calcium, magnesium, potassium, and sulphate were within prior value ranges (2018–2023), while chloride was lower.
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Dissolved oxygen (mg/L) | 2.51 (1.71–7.35) | 2018–2023 (7) |
| 001 | pH | 7.04 (6.86–7.05) | 2018–2023 (5) |
| 001 | Specific conductivity (µS/cm) | 661 (662–764) | 2018–2023 (6) |
| 001 | Temperature (°C) | 13.6 (13.2–19.6) | 2018–2023 (9) |
| 001 | Total dissolved solids (mg/L) | 429.5 (430.0–497.0) | 2018–2023 (6) |
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Alkalinity (CaCO3) | 295 (285–390) | 2018–2023 (6) |
| 001 | Calcium (Ca) | 52 (18–56) | 2018–2023 (6) |
| 001 | Chloride (Cl) | 2 (5–61) | 2018–2023 (6) |
| 001 | Magnesium (Mg) | 70 (48–90) | 2018–2023 (6) |
| 001 | Potassium (K) | 0.8 (0.1–1.6) | 2018–2023 (6) |
| 001 | Sulphate (SO4) | 8 (3–9) | 2018–2023 (6) |
Oak Spring
Highlights: The spring contained water when we visited and was wet over 80% of the days measured in WY2024. However, the springbrook was much shorter than in prior years, and the plunge pool was completely dry.
Oak Spring (Figures 7 and 8) is a rheocrene spring (a spring that emerges into one or more stream channels) originating from several distinct orifices in an east-facing drainage lined with oak and juniper, about 1 km northwest of the Carlsbad Caverns Visitor Center. The primary orifice seeps cool, clear water from a bedrock seam inside the drainage, where a man-made rock dam confines the flow into a crescent-shaped pool. Additional seeps produce flow along the bedrock walls in the drainage and contribute to a plunge pool further down the channel. The WY2024 visit occurred on 01 March 2024, and the spring contained water.
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Site Condition
In WY2024, we rated Oak Spring slightly disturbed by drying based on the complete drying of a plunge pool that previously held water and the presence of upland species in the riparian area (rated undisturbed to moderately disturbed in the past; Figure 9). We rated the spring slightly disturbed by fire with charred stumps in the vicinity (rated undisturbed to slightly disturbed in the past); and moderately disturbed by flow modification related to pipes, rock walls, and dams (rated undisturbed to highly disturbed in the past). No other natural or human-caused disturbances were observed at Oak Spring in WY2024.
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As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Oak Spring in WY2024. We observed two species of invasive non-native plants at the spring: evenly distributed patches of Bermudagrass (Cynodon dactylon, evenly distributed patches to a matrix observed in 2017–2023) and scattered patches of horehound (Marrubium vulgare, scattered patches to evenly distributed patches observed in 2017–2023).
We observed two obligate/facultative wetland plant species: maidenhair fern (Adiantum sp., a fern observed in 2018–2023) and a sedge (Carex sp., observed in 2018–2023).
eDNA Inventory of Rare and Invasive Species and Pathogens
In WY2024, five water samples were collected from Oak Spring. None of our target organisms were detected, similar to WY2023.
Water Quantity
Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 10). The temperature sensor indicated that Oak Spring was wetted (contained water) for 126 of 153 days (82.4%) measured in WY2024 up to the visit. In prior water years, the spring was wetted 69.9–100% of the days measured across entire years.
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Discharge was not measured in WY2024 because of a lack of measurable surface flow. Discharge estimates have ranged from 0.4–0.6 L/min (0.1–0.2 gal/min) in past years (Table 5). Wetted extent was evaluated using a method for flowing water. The total springbrook length was 2.4 m (7.9 ft), which was notably shorter than the previously recorded range of 10.9–43.6 m (35.8–143.0 ft). Average springbrook width was 127.2 cm (50.1 in), and depth was 1.8 cm (0.7 in). Width was greater than in prior years, while depth remained within the historical range (Table 6).
| Sampling Location | WY2024 Mean (Range of Prior Means) |
Prior Years Measured (# of Visits with Measurements) |
|---|---|---|
| 004 | c.n.s. (0.4–0.6) | 2018–2019 (2) |
| Measurement | WY2024 Value (Range of Prior Values/Means) |
Prior Years Measured (# of Visits with Measurements) |
|---|---|---|
| Width (cm) | 127.2 ± 52.3 (26.4–64.5) | 2018–2023 (6) |
| Depth (cm) | 1.8 ± 2.4 (0.4–2.1) | 2018–2023 (6) |
| Length (m) | 2.4 (10.9–43.6) | 2018–2023 (6) |
Water Quality
Core water quality (Table 7) and water chemistry (Table 8) data were collected at the primary sampling location in WY2024. Specific conductivity, pH, and total dissolved solids were within the ranges of prior measurements, while dissolved oxygen and water temperature were lower than in prior years. The values for calcium, chloride, magnesium, potassium, and sulphate were within the ranges previously recorded, and the alkalinity level was slightly lower.
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Dissolved oxygen (mg/L) | 2.75 (4.64–8.02) | 2019–2023 (4) |
| 001 | pH | 7.80 (7.75–8.12) | 2018–2023 (4) |
| 001 | Specific conductivity (µS/cm) | 558.0 (525.0–594.8) | 2018–2023 (5) |
| 001 | Temperature (°C) | 8.4 (8.7–15.8) | 2018–2023 (8) |
| 001 | Total dissolved solids (mg/L) | 362.7 (342.0–389.0) | 2018–2023 (6) |
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Alkalinity (CaCO3) | 240 (250–270) | 2018–2023 (6) |
| 001 | Calcium (Ca) | 50 (46–64) | 2018–2023 (6) |
| 001 | Chloride (Cl) | 5 (2–31) | 2018–2023 (6) |
| 001 | Magnesium (Mg) | 40 (0–65) | 2018–2023 (6) |
| 001 | Potassium (K) | 1.3 (0.5–1.7) | 2018–2023 (6) |
| 001 | Sulphate (SO4) | 0 (0–21) | 2018–2023 (6) |
Slaughter Pot Hole
Highlights: The spring contained water when we visited, but we have no persistence data for the year. The wetted area was similar to prior years. We observed one new invasive plant species: Lehmann lovegrass.
Slaughter Pot Hole (Figures 11 and 12) is a tinaja (a small pool in a rock basin or impoundment in bedrock) located in the upper elevations of Slaughter Canyon. The north, east, and west sides of the pool have sloping, slickrock walls, and the southwest side has a gentler slope that opens to a dry cobblestone wash where the Slaughter Canyon Trail passes through. The WY2024 visit occurred on 04 March 2024, and the spring contained water.
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Site Condition
No natural or human-caused disturbances were observed at Slaughter Pot Hole in WY2024.
As in past years, we did not observe invasive non-native crayfish or American bullfrog (Rana catesbeiana) at Slaughter Pot Hole in WY2024. We observed two species of invasive non-native plants at the spring: 1–5 Lehmann lovegrass plants (Eragrostis lehmanniana, not previously observed) and 1–5 common mullein plants (Verbascum thapsus, 1–5 plants observed in 2017–2018). We did not observe any obligate/facultative wetland plants.
eDNA Inventory of Rare and Invasive Species and Pathogens
In WY2024, four water samples were collected from Slaughter Pot Hole. None of our target organisms were detected, similar to WY2023.
Water Quantity
Sensors are deployed and data are downloaded during our annual visit; the dates of these visits are indicated by black diamonds in the persistence graph (Figure 13). Temperature sensor data are missing for the primary sampling location at Slaughter Pot Hole because the sensor was moved to a new sampling location, so there is no estimate of persistence for WY2024. In prior water years, the spring was wetted 46.2–100% of the days measured across entire years.
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As in past years, there was no measurable discharge from the tinaja. Slaughter Pot Hole was evaluated using a method for standing water. Width averaged 195.5 cm (77.0 in), length averaged 3.04 m (9.97 ft), and depth averaged 68.3 cm (26.9 in), all of which were within the ranges of prior measurements over the last seven years (Table 9).
| Measurement | WY2024 Mean (Range of Prior Means) |
Prior Years Measured (# of Visits with Measurements) |
|---|---|---|
| Width (cm) | 195.5 ± 44.0 (63.2–404.3) | 2017–2023 (7) |
| Depth (cm) | 68.3 ± 55.6 (24.3–109.5) | 2017–2023 (7) |
| Length (m) | 3.04 ± 1.01 (0.96–4.46) | 2017–2023 (7) |
Water Quality
Core water quality (Table 10) and water chemistry (Table 11) data were collected at the primary sampling location in WY2024. All water quality and chemistry parameters were within the ranges of prior measurements.
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Dissolved oxygen (mg/L) | 10.82 (0.56–17.40) | 2018–2023 (6) |
| 001 | pH | 8.92 (8.91–9.51) | 2018–2023 (5) |
| 001 | Specific conductivity (µS/cm) | 335.4 (182.4–644.0) | 2018–2023 (6) |
| 001 | Temperature (°C) | 12.1 (10.6–17.0) | 2018–2023 (8) |
| 001 | Total dissolved solids (mg/L) | 217.9 (118.0–419.0) | 2018–2023 (6) |
| Sampling Location | Parameter | WY2024 Value (Range of Prior Values) |
Prior Years Measured (# of Measurements) |
|---|---|---|---|
| 001 | Alkalinity (CaCO3) | 150 (90–350) | 2017–2023 (7) |
| 001 | Calcium (Ca) | 38 (22–54) | 2017–2023 (7) |
| 001 | Chloride (Cl) | b.d.l. (b.d.l.–12) | 2017–2023 (7) |
| 001 | Magnesium (Mg) | 18 (b.d.l.–58) | 2017–2023 (7) |
| 001 | Potassium (K) | 7.2 (2.3–36.0) | 2017–2023 (7) |
| 001 | Sulphate (SO4) | 0 (b.d.l.–6) | 2017–2023 (7) |
Upper East Grammer Spring
Highlights: The spring contained water when we visited. It was mostly wet in the fall and dry in the winter and early spring of WY2024. The wetted area was similar to prior years. We observed one new invasive plant species: Lehmann lovegrass.
Upper East Grammer Spring (Figures 14 and 15) is a rheocrene spring (a spring that emerges into one or more stream channels) located in a south-facing side drainage of Walnut Canyon that has ranged from 16.5 to 43.5 m (54.1–142.7 ft) in length in recent years. The spring is a slow seep that emerges from a rounded limestone bedrock seam inside the rocky drainage. It forms shallow pools in shaded areas and flows subsurface intermittently. The WY2024 visit occurred on 01 March 2024, and the spring contained water.
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